815633 - mx-live checking with DNS timeout should return 504, not 500

Status: VERIFIED FIXED

(Infrastructure & Operations Graveyard :: WebOps: Labs, task)

Description

[Mike Kaply [:mkaply]]

Sorry, I have no idea if this is the right bug component.

Thunderbird uses the mx-live.mozillamessaging.com server do do mx server checks for domains.

I've found a case where it fails in a strange way:

https://mx-live.mozillamessaging.com/dns/mx/eb.de
causes an internal server error.

https://mx-live.mozillamessaging.com/dns/mx/web.de works fine
https://mx-live.mozillamessaging.com/dns/mx/b.de works fine.

Comment 1

[Ben Bucksch (:BenB)]

My actual result:
The page takes 2 minutes to load, then results in a "Service unavailable" webpage.

This is just the DNS server of eb.de not responding. When I do
dig mx eb.de
it also stalls for 1 minute, then dig says "connection timeout".

So, the webservice reacts properly. Just the return code 500 is wrong, which is by definition an intenal server error, which this is not. I would change the return code to "504 Gateway timeout", because that seems to be *exactly* out case here.

http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
"
10.5.5 504 Gateway Timeout

The server, while acting as a gateway or proxy, did not receive a timely response from the upstream server specified by the URI (e.g. HTTP, FTP, LDAP) or some other auxiliary server (e.g. DNS) it needed to access in attempting to complete the request.

      Note: Note to implementors: some deployed proxies are known to
      return 400 or 500 when DNS lookups time out.
"

Good spec.

Comment 2

[Mark Banner (:standard8)]

This should live in mozilla.org now.

Comment 3

[Shyam Mani [:fox2mike]]

Gozer, no idea where this lives or how this can be patched/fixed.

Comment 4

[Philippe M. Chiasson (:gozer)]

Landed the code change on github https://github.com/gozer-mozilla/http-mx/commit/64c2b05d30ac131cf82dda22c598f5b172692fb7

The code itself runs on a labs VM at the moment, I'll patch that one up shortly.

Comment 5

[Philippe M. Chiasson (:gozer)]

Deployed

Comment 6

[Mike Kaply [:mkaply]]

Looks good.